There's one requirement to form a Ghostbusters squad. Hint: It starts with "P."

It's a PhD. Venkman, Stantz, and Spengler had one. So do new Ghostbusters Dr. Abby Yates (Melissa McCarthy), Dr. Jillian Holtzmann (Kate McKinnon), and Dr. Erin Gilbert (Kristen Wiig). And like the dudes, Dr. Gilbert even teaches at Columbia.

But here's where the differences start. Columbia fired Venkman for being a "poor scientist." Gilbert is a great one — and the old, white guy in charge still won't accept her. "About your clothes," he scowls. "Too sexy for academia?" she blushes, looking down at her prim blouse and boxy suit. "What is it?" she pleads. He walks off without finishing his weak excuse. She's disappointed him just by existing.

Welcome to the last two years of writer-director Paul Feig's life. When he and cowriter Katie Dippold announced their all-female Ghostbusters reboot, he probably imagined making a fun, straightforward romp. Then the internet — or really, fleas bedeviling the internet — attacked. They accused Feig's four fantastic comedians of ruining their childhood, a claim that, when made by grown men, also endangers their adulthood.

It's on.

Feig's finished film is a middle finger to the screaming brobabiez. He’s always boosted women — last summer’s underestimated Spy was a delight — but now he’s attacking men. If girls can't be Ghostbusters, then here, guys can't do anything. Every dude in the film is a bully, a loser, or a dummy, from the jerks who fire Yates, Holtzmann, and Gilbert from their professorships to the YouTube commenters who react to their videos by scrawling, “Ain’t no bitches gonna fight no ghosts.” Sighs Yates, “You’re not supposed to be listening to what crazy people say online.” While the lads hired Annie Potts’s sharp secretary Janine, the ladies are saddled with himbo receptionist Kevin (Chris Hemsworth), who’s only slightly smarter than a cactus. Kevin can't even properly answer the phone, a double-edged gag that makes men look helpless while underscoring that female heroes have to do everything themselves.

And that's just an amuse-bouche. Feig resurrects an original cast member for a cameo — hooray! — only to scuttle hopes of a follow-up "real" sequel by writing him a new character: a mansplaining sexist who barges into the ladies' office, orders them around, cuts them off, and gets snippy when they lose patience. "Why are you pretending to catch ghosts?" he accuses. Wiig's needy Gilbert is desperate for his approval. The other three, who now count New York history expert Patty (Leslie Jones), couldn't care less. Glares McCarthy, "It's really easy to sit there and be the naysayer when you don't have to do anything."

But Feig saves his favorite jab for Ghostbusters's villain. Is it another powerful demigod like Zuul? Or a medieval Hungarian sorcerer? Nope. It's just janitor Rowan (Neil Casey), a pathetic social reject with anger issues. You know, like the creeps behind the computers.

But enough about scary humans. We're supposed to be here for ghosts. These updated spooks are shiny, glowing, and almost too gorgeous. They look so expensive that when poor foam rubber Slimer shows up, he's outclassed. Then again, in the last 22 years, everything in New York has jacked up its price. That old firehouse now goes for $21,000 a month. Sorry, girls — in 2016 you've gotta live above a Chinese fast-food joint.

As for the busting, it's fine. Protons fire, spirits writhe, and Stage 4 apparitions vomit ectoslime directly at the screen. According to paranormal experts, women make good Ghostbusters because they have the empathy to communicate with the dead. If true, that skill goes ignored. The action is rehashed favorite hits, done with previous director turned producer Ivan Reitman's blessing. We need another giant, pasty monster smashing up Manhattan as much as we need Fall Out Boy's god-awful cover of Ray Parker Jr.’s Ghostbusters theme. The more Feig apes the past, the more we're reminded that the original is irreplaceable. Reitman could have remade it shot-for-shot with the 1984 cast and fans would still be underwhelmed.

Yet when Feig makes the fight sequences his own, we get a gorgeous shot of two of the stars tumbling into a spectral wormhole. We get ladies licking their plasma-pistols and shooting ghouls in the crotch. Alas, Feig's ambitious attempt at a giant dance number got killed. At least it lives on in the credits. And I couldn't help but snicker that a side effect of Rowan's evil plan transforms modern Manhattan into a retro nightmare, with old storefronts and even older ghouls. Our leads are rewound to pre-’70s New York, back before Pam Grier became the first female action hero. To save the future, they have to destroy the past — including the Ghostbusters logo. It's like Feig is hunting a second kind of ghost: the moth-eaten macho mind-set that should have died decades ago.

Still, the big CG sequences are less captivating than simply watching the four ladies kick it with a pizza. Wiig and McCarthy nestle into their comfortable roles as the soft-spoken priss and the bustling madwoman, leaving room for Jones to barge in with her big punch lines.

But keep your eyes on the background. That's where Jones's Saturday Night Live costar McKinnon lurks, quietly transforming herself into a movie star. McKinnon gets half the lines of Wiig and McCarthy, yet she dominates our attention. She takes up space, slinging her arms on people's shoulders and staring at the camera as if daring us to blink. She's electric and fearless. When she sprays a fire extinguisher, McKinnon throws her head back in ecstasy. The erotic gag isn't for our pleasure, it's for her own damned amusement: Busting makes her feel great. She's a weirdo enjoying herself without giving a fuck what anybody thinks — something Ghostbusters should have been able to do all along.

[Illustration: Kurt Woerpel]